A variety of passive vehcile occupant restraint belt systems have heretofore been proposed in which the outboard end of a restraint belt is moved forward away from the occupant when the door is opened and is moved rearwardly to a restraint configuration when the door is closed. For example, some proposed systems include a lap belt which leads from an inboard location adjcent the lower rear portion of the vehicle seat across the seat to a movable guide which slides along a guide rail on the inside of the door between an occupant-restraining location near the lower rear corner of the door and an occupant-releasing location near the window sill somewhere between the forward and rearward ends of the door. Other systems comprise a shoulder belt which leads from an inboard location adjacent the lower rear portion of the seat up to a movable guide that moves along a guide rail at the edge of the roof above the vehicle door. Other systems employ both the lap belt and the seat belt. In still another type of passive restraint belt system, often called a three-point system, the ends of a shoulder belt and a lap belt that are located on the inboard side of the seat occupant when the belts are in the occupant-restraining configuration are joined to each other and to a control ring at the end of a control belt which leads from an emergency locking retractor adjacent the lower rear portion of the inboard side of the seat.
In almost all passive vehicle occupant restraint belt systems of the types referred to above, there is a fixed location at the inboard lower rear portion of the seat from which a control belt, lap belt or shoulder belt leads. When any of these systems are used in association with a seat having a back which folds forwardly, the best example of which is the front seat of a two door automobile having a rear seat, the lap belt, shoulder belt or control belt interfers with the forward folding of the seat, even when the belt is in the releasing configuration. When the door is open and the passive belt is in the releasing configuration and a passenger in the rear seat pushes the seat back of the front seat forwardly, the seat back will contact the front seat restraint belt or control belt, especially the inboard part. Ordinarily, an additional length of the belt will be drawn from a retractor so that the seat back can be pushed further forward, but the result of such contact and movement is a wearing action on both the belt and the part of the seat back which contacts the belt. Moreover, additional forces are required to be exerted by the rear seat passenger to push the seat back forward so he can enter or leave the vehicle.
Another problem with passive restraint belt systems used in connection with seats having forwardly folding backs is that it sometimes happens that the seat back is folded forwardly when someone tries to open or close the door. In some three-point systems, the control ring sometimes catches on the seat back and jams the mechanism which moves the belts and prevents the door from being opened or closed as long as the control ring is caught.